Back To Top
The most common type of water supply piping is copper piping. This piping is used to supply water service from the municipal street connection to the dwelling, as well as from the dwelling to the interior of the house. It's important that copper piping not be kinked as this will drastically reduce water flow. Residential service piping is typically 3/4 inch diameter. Larger homes may have 1 inch or greater. The horizontal supply piping within the structure is generally 3/4 inch with 1/2-inch risers to plumbing fixtures (sink, toilet, etc). Smaller homes or homes with one bathroom may have 1/2-inch supply piping.
Copper has long been a very dependable material. However, if the home is supplied by a well and the water is acidic or has a low pH level, it will tend to eventually corrode and degrade the copper. Subsequently, when the walls of the pipe wear thin, the failures will look like tiny, round, green patina stains. If these stains are ignored, water may spray through the hole in the center of the round stain. This problem, generally due to the acidic water, can be neutralized with a mechanical water softener or filter.
Water hammer, otherwise referred to as the banging noises heard when water flow is abruptly stopped, is not unusual in metal pipe configurations, such as copper or steel. The momentum of the water flow stoppage makes the noise. One solution is to provide an air cushion or shock absorber that will soften the movement or momentum of the water. Some water supply systems have air tubes or diaphragm appliances installed in the piping system to prevent hammering.
Polybutylene Piping (PB)
Polybutylene piping is flexible, gray, plastic piping with epoxy secured joints, or inserted fittings and metal crimp rings. This material has been known to be defective at the junctions. Barbed brass or copper insert fittings with crimp ring joints are generally more dependable than the epoxy joints. The joints are vulnerable to chlorine in the water, which causes deterioration. The insert fittings have been in use since 1978 and may still in use today. However, production and installation pretty much ceased after 1995.
Most municipalities do not allow certain types of PB piping to be used for residential potable water because of their potential for leaking. There have been individual, as well as class action lawsuits, concerning certain manufacturers of this product.
The major manufacturers of PB piping were Quest and Vangard. Since they can no longer purchase the resins necessary to produce this material, they have switched to production of PEX. This is is a type of Polybutylene that is acceptable for potable water use in most areas.
A second type of polybutylene piping is “Big Blue". This piping is typically utilized in the main water service to the house. Its name was derived from the color of the material. The material is 1 1/2 to 2 inches in diameter and was rated for cold-water installation only. The major problems that surfaced with this type of PB piping are related to poor installation practices.
Galvanized Steel Water Service and Supply Piping
Galvanized steel piping is still in use, however, not installed any longer in modern construction. It oxidizes from the inside out. The oxidation (rust) reduces the interior diameter of the pipe, restricting the flow of water, and usually begins leaking at threaded joints where the pipes are joined. This is analogous to hardening of the arteries in humans. Adequate water supply can normally be restored, to some extent, by replacing the horizontal supply piping in the basement (assuming they are accessible) with copper. Replacing the vertical risers in the walls is much more difficult and expensive than accessible horizontal piping. Replacing all of the older galvanized steel piping would be the most desirable solution, but also the most expensive.
If the supply piping from the municipal water lines is galvanized steel, it is likely that the service piping is also galvanized steel. Galvanized steel piping fails sooner at the heavier used fixtures (i.e. the kitchen sink and the main bathroom). Failures are usually related to the amount of oxygen that is present. The more a fixture is used, the more water (and oxygen) is present, which corrodes/oxidizes the piping at a greater rate.
First clues of failure in the piping are roundish rust growths, commonly called rust warts, on the outside of the pipe. These are failures that have come through the pipe. It is not unusual for the corrosion to seal the failure temporarily.
Polyvinyl Chloride Piping (PVC)
PVC piping is approved for cold water only. Chlorinated polyvinyl chloride (CPVC) is approved for cold water and may be used for hot water, but not over 140° Fahrenheit. PVCs are joined with a primer and solvent cement. PVC piping is not a conductor and cannot be used for an electrical ground.
Polyethylene Pipe (PE)
Polyethylene piping is typically used as service piping. Generally black in color, it is a flexible material that is easier to install than most other service pipings. Joints in PE piping may not be made with adhesives or solvent cements. Joints should have two stainless steel band clamps, but the connection to metal (such as copper) is typically made with one clamp. The fittings have a smaller interior diameter than the piping. Therefore, PE must be sized based upon the fittings. This material is approved for cold water installation only and is very often found in well water applications.
There is very little lead supply piping in use, however, you may see some lead service piping in 80+ old construction, urban or rural. The prominent concern is the probable 6-inch to 8-inch municipal main in the street that is also lead. Historically, only trace elements of lead are measurable in residential domestic water systems.
Threaded brass is uncommon, however, you may still see it in homes built before 1940. The same things that affect copper tend to impact brass.
Back To Top
The shutoff valve should be on the supply or cold side. Typically, there is no shut off valve on the “out” or “hot” side.Valve
Find the water shut off valve at the water supply to the boiler, and if the unit supplies domestic hot water, there will also be a shut off to the domestic water coil.
Exterior Hose Bibs
All hose bibs should be checked to insure that water flows from them. There are two types of hose bibs:
The anti-frost hose bib is a unit that goes through the wall, with the seat of the valve located in the heated portion of the house (approximately 8 to 14 inches in from the exterior). This usually prevents the faucet from freezing and rupturing. It is always necessary to remove garden hoses from hose bibs in cold months, to prevent freezing and damage not only to the hose, but to that section of the pipe immediately inside the exterior wall. The sections have been know to contain residual water and are subject to freezing if not allowed to fully drain.
Sill cock or Old Style Soldered
This is the older, standard hose bibb. The air bleeder at the valve should be opened in colder months, to allow the water to drain out.
Vents and Traps
Back To Top
Venting is necessary to provide air to displace the water that is moving down and through the drainage system.
Plumbing vents at the exterior should be at least 6 inches above the roofline, on the high side of the penetration. Vents must be at least 10 feet from windows. “In the wall” or “under-the-counter” air admittance vents (AAV) may not be permitted and must be authorized by local code. A cooking island in a kitchen, with a sink, often will have a vent of this type under the counter. Vents should be within 42 inches of the fixture being vented.
Traps prevent odorous sewage gases from entering the house through the sink and tub drains. There are two basic types of traps: (one acceptable, one not acceptable)
The full “S” trap or 3/4 “S” trap should not be used in plumbing installations. These traps are almost impossible to vent properly. The 3/4 “S’ trap forms a perfect siphon. “P” traps discharge is horizontal rather than vertical. The liquid seal is dependable and acceptable.
The problem with “S” traps is that the waste water may siphon out, causing the trap to lose its liquid seal. Every plumbing fixture, such as sinks, tubs and showers, should have a proper trap. Toilet traps are built into the bowl of the toilet. If a sink, etc. does not have a trap, trace the drain for other inequities that may be present (i.e. draining into a sump pump, a dry well or to the exterior surface). In older construction, there are thousands of “S” traps in use. Older building codes did not address this issue. In many cases it may be very difficult to change an “S” trap to a “P” trap.
Municipal waste systems are designed and controlled by the governing municipality. The users pay a fee for usage; typically the fee is based on the amount of water the occupants of the home or building use.
Back To Top
Types of unauthorized systems
Dumping raw or untreated sewage into a body of water, such as a pond, river, lake, stream, etc. Illegal discharge of gray water to the exterior (i.e. ground, ravine, ditch, etc.); dumping ground water from a sump pump or air conditioning condensate into a sewage line. Note: There are acceptable gray water drainage systems. Check with local authorities. Waste water is sometimes routed from the laundry into the sump pit and then discharged by the sump pump to the exterior.
Main Clean Out
The main clean out is frequently located at the wall or the slab close to where the sewage line exits the property (i.e. if the sewer line is in the street, the cleanout will probably be located on the wall of the house that is closest to the street). The main waste clean out should be located at the base of the main waste discharge line. This line is typically 3-4 inches in diameter. Occasionally, a toilet may be the best access to the sewer line and may have to be removed, if it is located in the vicinity of the sewage line as it exits the property. This is in lieu of a cleanout.